RenderView::RenderView(Document* document)
    : RenderBlockFlow(document)
    , m_frameView(document->view())
    , m_selectionStart(0)
    , m_selectionEnd(0)
    , m_selectionStartPos(-1)
    , m_selectionEndPos(-1)
    , m_maximalOutlineSize(0)
    , m_pageLogicalHeight(0)
    , m_pageLogicalHeightChanged(false)
    , m_layoutState(0)
    , m_layoutStateDisableCount(0)
    , m_renderQuoteHead(0)
    , m_renderCounterCount(0)
{
    // init RenderObject attributes
    setInline(false);

    m_minPreferredLogicalWidth = 0;
    m_maxPreferredLogicalWidth = 0;

    setPreferredLogicalWidthsDirty(MarkOnlyThis);

    setPositionState(AbsolutePosition); // to 0,0 :)
}

void RenderRegion::computePreferredLogicalWidths()
{
    ASSERT(preferredLogicalWidthsDirty());

    if (!isValid()) {
        RenderBlockFlow::computePreferredLogicalWidths();
        return;
    }

    // FIXME: Currently, the code handles only the <length> case for min-width/max-width.
    // It should also support other values, like percentage, calc or viewport relative.
    m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = 0;

    const RenderStyle& styleToUse = style();
    if (styleToUse.logicalWidth().isFixed() && styleToUse.logicalWidth().value() > 0)
        m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = adjustContentBoxLogicalWidthForBoxSizing(styleToUse.logicalWidth().value());
    else
        computeIntrinsicLogicalWidths(m_minPreferredLogicalWidth, m_maxPreferredLogicalWidth);

    if (styleToUse.logicalMinWidth().isFixed() && styleToUse.logicalMinWidth().value() > 0) {
        m_maxPreferredLogicalWidth = std::max(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse.logicalMinWidth().value()));
        m_minPreferredLogicalWidth = std::max(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse.logicalMinWidth().value()));
    }

    if (styleToUse.logicalMaxWidth().isFixed()) {
        m_maxPreferredLogicalWidth = std::min(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse.logicalMaxWidth().value()));
        m_minPreferredLogicalWidth = std::min(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(styleToUse.logicalMaxWidth().value()));
    }

    LayoutUnit borderAndPadding = borderAndPaddingLogicalWidth();
    m_minPreferredLogicalWidth += borderAndPadding;
    m_maxPreferredLogicalWidth += borderAndPadding;
    setPreferredLogicalWidthsDirty(false);
}

void RenderHTMLCanvas::canvasSizeChanged()
{
    IntSize canvasSize = toHTMLCanvasElement(node())->size();
    LayoutSize zoomedSize(canvasSize.width() * style()->effectiveZoom(), canvasSize.height() * style()->effectiveZoom());

    if (zoomedSize == intrinsicSize())
        return;

    setIntrinsicSize(zoomedSize);

    if (!parent())
        return;

    if (!preferredLogicalWidthsDirty())
        setPreferredLogicalWidthsDirty();

    LayoutSize oldSize = size();
    updateLogicalWidth();
    updateLogicalHeight();
    if (oldSize == size())
        return;

    if (!selfNeedsLayout())
        setNeedsLayoutAndFullPaintInvalidation();
}

void RenderTextControl::computePreferredLogicalWidths()
{
    ASSERT(preferredLogicalWidthsDirty());

    m_minPreferredLogicalWidth = 0;
    m_maxPreferredLogicalWidth = 0;

    if (style().logicalWidth().isFixed() && style().logicalWidth().value() >= 0)
        m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = adjustContentBoxLogicalWidthForBoxSizing(style().logicalWidth().value());
    else
        computeIntrinsicLogicalWidths(m_minPreferredLogicalWidth, m_maxPreferredLogicalWidth);

    if (style().logicalMinWidth().isFixed() && style().logicalMinWidth().value() > 0) {
        m_maxPreferredLogicalWidth = std::max(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(style().logicalMinWidth().value()));
        m_minPreferredLogicalWidth = std::max(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(style().logicalMinWidth().value()));
    }

    if (style().logicalMaxWidth().isFixed()) {
        m_maxPreferredLogicalWidth = std::min(m_maxPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(style().logicalMaxWidth().value()));
        m_minPreferredLogicalWidth = std::min(m_minPreferredLogicalWidth, adjustContentBoxLogicalWidthForBoxSizing(style().logicalMaxWidth().value()));
    }

    LayoutUnit toAdd = borderAndPaddingLogicalWidth();

    m_minPreferredLogicalWidth += toAdd;
    m_maxPreferredLogicalWidth += toAdd;

    setPreferredLogicalWidthsDirty(false);
}

void RenderImage::imageChanged(WrappedImagePtr newImage, const IntRect* rect)
{
    if (documentBeingDestroyed())
        return;

    if (!m_imageResource)
        return;

    if (newImage != m_imageResource->imagePtr())
        return;

    // Per the spec, we let the server-sent header override srcset/other sources of dpr.
    // https://github.com/igrigorik/http-client-hints/blob/master/draft-grigorik-http-client-hints-01.txt#L255
    if (m_imageResource->cachedImage() && m_imageResource->cachedImage()->hasDevicePixelRatioHeaderValue())
        m_imageDevicePixelRatio = 1 / m_imageResource->cachedImage()->devicePixelRatioHeaderValue();

    // If the RenderImage was just created we don't have style() or a parent()
    // yet so all we can do is update our intrinsic size. Once we're inserted
    // the resulting layout will do the rest of the work.
    if (!parent()) {
        updateIntrinsicSizeIfNeeded(m_imageResource->intrinsicSize());
        return;
    }

    RenderReplaced::imageChanged(newImage, rect);

    ASSERT(isRooted());

    LayoutSize oldIntrinsicSize = intrinsicSize();
    LayoutSize newIntrinsicSize = m_imageResource->intrinsicSize();
    updateIntrinsicSizeIfNeeded(newIntrinsicSize);

    bool imageSourceHasChangedSize = oldIntrinsicSize != newIntrinsicSize;
    if (imageSourceHasChangedSize)
        setPreferredLogicalWidthsDirty();

    // If the actual area occupied by the image has changed and it is not constrained by style then a layout is required.
    bool imageSizeIsConstrained = style()->logicalWidth().isSpecified() && style()->logicalHeight().isSpecified();

    // FIXME: We only need to recompute the containing block's preferred size if the containing block's size
    // depends on the image's size (i.e., the container uses shrink-to-fit sizing).
    // There's no easy way to detect that shrink-to-fit is needed, always force a layout.
    bool containingBlockNeedsToRecomputePreferredSize = style()->logicalWidth().isPercent() || style()->logicalMaxWidth().isPercent()  || style()->logicalMinWidth().isPercent();

    if (imageSourceHasChangedSize && (!imageSizeIsConstrained || containingBlockNeedsToRecomputePreferredSize)) {
        setNeedsLayout();
        return;
    }

    // The image hasn't changed in size or its style constrains its size, so a paint invalidation will suffice.
    if (everHadLayout() && !selfNeedsLayout()) {
        // The inner content rectangle is calculated during layout, but may need an update now
        // (unless the box has already been scheduled for layout). In order to calculate it, we
        // may need values from the containing block, though, so make sure that we're not too
        // early. It may be that layout hasn't even taken place once yet.
        updateInnerContentRect();
    }
}

void RenderScrollbarPart::computePreferredLogicalWidths()
{
    if (!preferredLogicalWidthsDirty())
        return;
    
    m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = 0;

    setPreferredLogicalWidthsDirty(false);
}

void RenderImage::paintInvalidationOrMarkForLayout(const IntRect* rect)
{
    ASSERT(isRooted());

    LayoutSize oldIntrinsicSize = intrinsicSize();
    LayoutSize newIntrinsicSize = m_imageResource->intrinsicSize();
    updateIntrinsicSizeIfNeeded(newIntrinsicSize);

    bool imageSourceHasChangedSize = oldIntrinsicSize != newIntrinsicSize;
    if (imageSourceHasChangedSize)
        setPreferredLogicalWidthsDirty();

    // If the actual area occupied by the image has changed and it is not constrained by style then a layout is required.
    bool imageSizeIsConstrained = style()->logicalWidth().isSpecified() && style()->logicalHeight().isSpecified();

    // FIXME: We only need to recompute the containing block's preferred size if the containing block's size
    // depends on the image's size (i.e., the container uses shrink-to-fit sizing).
    // There's no easy way to detect that shrink-to-fit is needed, always force a layout.
    bool containingBlockNeedsToRecomputePreferredSize = style()->logicalWidth().isPercent() || style()->logicalMaxWidth().isPercent()  || style()->logicalMinWidth().isPercent();

    if (imageSourceHasChangedSize && (!imageSizeIsConstrained || containingBlockNeedsToRecomputePreferredSize)) {
        setNeedsLayoutAndFullPaintInvalidation();
        return;
    }

    // The image hasn't changed in size or its style constrains its size, so a paint invalidation will suffice.
    if (everHadLayout() && !selfNeedsLayout()) {
        // The inner content rectangle is calculated during layout, but may need an update now
        // (unless the box has already been scheduled for layout). In order to calculate it, we
        // may need values from the containing block, though, so make sure that we're not too
        // early. It may be that layout hasn't even taken place once yet.
        updateInnerContentRect();
    }

    LayoutRect paintInvalidationRect;
    if (rect) {
        // The image changed rect is in source image coordinates,
        // so map from the bounds of the image to the contentsBox.
        paintInvalidationRect = enclosingIntRect(mapRect(*rect, FloatRect(FloatPoint(), m_imageResource->imageSize()), contentBoxRect()));
        // Guard against too-large changed rects.
        paintInvalidationRect.intersect(contentBoxRect());
    } else {
        paintInvalidationRect = contentBoxRect();
    }

    {
        // FIXME: We should not be allowing paint invalidations during layout. crbug.com/339584
        AllowPaintInvalidationScope scoper(frameView());
        DisableCompositingQueryAsserts disabler;
        invalidatePaintRectangle(paintInvalidationRect);
    }

    // Tell any potential compositing layers that the image needs updating.
    contentChanged(ImageChanged);
}

void RenderMathMLPadded::computePreferredLogicalWidths()
{
    ASSERT(preferredLogicalWidthsDirty());

    // Determine the intrinsic width of the content.
    RenderMathMLRow::computePreferredLogicalWidths();

    // Only the width attribute should modify the width.
    // We parse it using the preferred width of the content as its default value.
    LayoutUnit width = m_maxPreferredLogicalWidth;
    resolveWidth(width);
    m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = width;

    setPreferredLogicalWidthsDirty(false);
}

void RenderMathMLFraction::computePreferredLogicalWidths()
{
    ASSERT(preferredLogicalWidthsDirty());

    m_minPreferredLogicalWidth = 0;
    m_maxPreferredLogicalWidth = 0;

    if (isValid()) {
        LayoutUnit numeratorWidth = numerator().maxPreferredLogicalWidth();
        LayoutUnit denominatorWidth = denominator().maxPreferredLogicalWidth();
        m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = std::max(numeratorWidth, denominatorWidth);
    }

    setPreferredLogicalWidthsDirty(false);
}

void RenderReplaced::computePreferredLogicalWidths()
{
    ASSERT(preferredLogicalWidthsDirty());

    LayoutUnit borderAndPadding = borderAndPaddingWidth();
    m_maxPreferredLogicalWidth = computeReplacedLogicalWidth(false) + borderAndPadding;

    if (style()->maxWidth().isFixed())
        m_maxPreferredLogicalWidth = min<LayoutUnit>(m_maxPreferredLogicalWidth, style()->maxWidth().value() + (style()->boxSizing() == CONTENT_BOX ? borderAndPadding : ZERO_LAYOUT_UNIT));

    if (hasRelativeDimensions())
        m_minPreferredLogicalWidth = 0;
    else
        m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth;

    setPreferredLogicalWidthsDirty(false);
}

void RenderMathMLRoot::layout()
{
    for (auto& box : childrenOfType<RenderBox>(*this))
        box.layoutIfNeeded();

    int baseHeight = firstChild() && firstChild()->isBox() ? roundToInt(toRenderBox(firstChild())->logicalHeight()) : style().fontSize();
    int frontWidth = lroundf(gFrontWidthEms * style().fontSize());
    
    // Base height above which the shape of the root changes
    float thresholdHeight = gThresholdBaseHeightEms * style().fontSize();
    if (baseHeight > thresholdHeight && thresholdHeight) {
        float shift = std::min<float>((baseHeight - thresholdHeight) / thresholdHeight, 1.0f);
        m_overbarLeftPointShift = static_cast<int>(shift * gRadicalBottomPointXFront * frontWidth);
        m_intrinsicPaddingAfter = lroundf(gBigRootBottomPaddingEms * style().fontSize());
    } else {
        m_overbarLeftPointShift = 0;
        m_intrinsicPaddingAfter = 0;
    }
    
    int rootPad = lroundf(gSpaceAboveEms * style().fontSize());
    m_intrinsicPaddingBefore = rootPad;
    m_indexTop = 0;
    if (RenderBox* index = this->index()) {
        m_intrinsicPaddingStart = roundToInt(index->maxPreferredLogicalWidth()) + m_overbarLeftPointShift;

        int indexHeight = roundToInt(index->logicalHeight());
        int partDipHeight = lroundf((1 - gRootRadicalDipLeftPointYPos) * baseHeight);
        int rootExtraTop = partDipHeight + indexHeight - (baseHeight + rootPad);
        if (rootExtraTop > 0)
            m_intrinsicPaddingBefore += rootExtraTop;
        else
            m_indexTop = - rootExtraTop;
    } else
        m_intrinsicPaddingStart = frontWidth;

    // FIXME: We should rewrite RenderMathMLRoot to rewrite -webkit-flex-order to get rid of the need
    // for intrinsic padding. See https://bugs.webkit.org/show_bug.cgi?id=107151#c2.
    // FIXME: We should make it so that the preferred width of RenderMathMLRoots doesn't change during layout.
    // Technically, we currently only need to set the dirty bit here if one of the member variables above changes.
    setPreferredLogicalWidthsDirty(true);

    RenderMathMLBlock::layout();

    if (RenderBox* index = this->index())
        index->setLogicalTop(m_indexTop);
}

RenderView::RenderView(Document* document)
    : RenderFlexibleBox(document)
    , m_frameView(document ? document->view() : nullptr)
    , m_selectionStart(nullptr)
    , m_selectionEnd(nullptr)
    , m_selectionStartPos(-1)
    , m_selectionEndPos(-1)
    , m_renderCounterCount(0)
    , m_hitTestCount(0)
{
    // init RenderObject attributes
    setInline(false);

    m_minPreferredLogicalWidth = 0;
    m_maxPreferredLogicalWidth = 0;

    setPreferredLogicalWidthsDirty(MarkOnlyThis);

    setPositionState(AbsolutePosition); // to 0,0 :)
}

bool RenderReplaced::setNeedsLayoutIfNeededAfterIntrinsicSizeChange()
{
    setPreferredLogicalWidthsDirty(true);
    
    // If the actual area occupied by the image has changed and it is not constrained by style then a layout is required.
    bool imageSizeIsConstrained = style().logicalWidth().isSpecified() && style().logicalHeight().isSpecified();
    
    // FIXME: We only need to recompute the containing block's preferred size
    // if the containing block's size depends on the image's size (i.e., the container uses shrink-to-fit sizing).
    // There's no easy way to detect that shrink-to-fit is needed, always force a layout.
    bool containingBlockNeedsToRecomputePreferredSize =
        style().logicalWidth().isPercentOrCalculated()
        || style().logicalMaxWidth().isPercentOrCalculated()
        || style().logicalMinWidth().isPercentOrCalculated();
    
    bool layoutSizeDependsOnIntrinsicSize = style().aspectRatioType() == AspectRatioFromIntrinsic;
    
    if (!imageSizeIsConstrained || containingBlockNeedsToRecomputePreferredSize || layoutSizeDependsOnIntrinsicSize) {
        setNeedsLayout();
        return true;
    }

    return false;
}

void RenderReplica::computePreferredLogicalWidths()
{
    m_minPreferredLogicalWidth = parentBox()->width();
    m_maxPreferredLogicalWidth = m_minPreferredLogicalWidth;
    setPreferredLogicalWidthsDirty(false);
}